Performance of Closed Type Impeller Designed for Easy Manufacturability

The impeller of the semi-open type from a refrigerator unit is redesigned to improve efficiency and to reduce the pressure pulsations of the front case. Therefore, the closedtype impeller with outer shroud is chosen. Dimensions are scaled according to Cordier diagram with rotational speed preserved. The resulting geometry is constrained by requirement of easy manufacturability by injection moulding process. These constrains don't permit to improve efficiency by redesigning impeller.